Along with the constant progress of Science and Technology, the applications of smart card already became an essential part in people's life. Many applications, from the building entrance guard to the mobile telephone, from the public traffic card to the campus card, from the EMV bank card to the electronical identification, are closely linked to the smart card. With the popularity of the applications of the smart card, the functions of the smart card are required to be more and more diverse, which means the hardware technique should be improved continually and quickly. For example, the number of bits of the CPU is changed from the initial 8 to the widely used 16, and gradually being changed to 32; for the storage capacity, from the initial tens of bytes, to the tens of thousand, hundreds of thousand, and even to Million; for the type of memories, from the initial ROM, RAM and EEPROM to the current NOR FLASH, and then to the new generation of technique combining NOR FLASH and NAND FLASH; for the transmission interface, from the single interface ISO7816 to the high speed interface combining MMC or USB for several channels.
Although the hardware process has been improved quickly, the structure of the chip operating system of the smart card has no bigger change. FIG. 1 shows the framework of the software and hardware of the present smart card, from which we can see that the framework of the software and hardware of the present smart card consists of the hardware platform, the self-defined Card Operating System (COS) and the application of the smart card, wherein, the COS and the application work as one body in most conditions with no evident bound between them. In this structure, since the COS is developed for a special hardware platform, it should be correspondingly modified when the hardware platform changes. FIG. 2 is the schematic diagram of the operating system of the present smart card, from which we can see that the operating system is generally a relatively simple foreground/background system or super-loop system which is an infinite loop, and in the loop, corresponding functions are called to perform the corresponding operations, for example, the interrupt service routine for asynchronous event, and the critical operation with strong time relativity is guaranteed by the interrupt service. Since the information offered by the interrupt service can only be processed until the background routine reaches this information. This system is poorer than it practically is on terms of the betimes of the system processing the information. The response time in the worst case depends on the processing time of the whole loop. Since the time is not constant, the precise time that the routine passes a special part can not be decided. Moreover, if the routine is modified, the time sequence of the loop can be affected.
In addition, because of the super-loop structure of the conventional COS, it is complicated for the system to manage several different applications at the same time, thus one card with the conventional structure is only for one application, which means the COS is generally responsible for one application. Therefore the application and the COS are developed together at most cases and there is no evident bound between them.
With a diversity of hardware platforms at the bottom layer of the smart card, the framework of the software and hardware of the traditional smart card can not meet the needs, and a new COS capable of processing large capacity, several channels and several applications with harder real-time is desired.